package cn.tedu.v6;

import java.io.*;
import java.net.BindException;
import java.net.ServerSocket;
import java.net.Socket;
import java.util.*;

/**
 * Version 6  在线用户列表，统计上线名称
 *            消息转发  ---交互---服务器端文字
 */
public class Server {
    private ServerSocket serverSocket;
    private static final Integer PORT=0202;
    private List<PrintWriter> allOut=new ArrayList<>();
    //1.存储在线客户：onlineUsers
    private List<String> onlineUsers=new ArrayList<>();

    private Map<String,String> userDatabase;
    public Server(){
        try {
            serverSocket=new ServerSocket(PORT);
            userDatabase=new HashMap<>();
            userDatabase.put("朱","123456");
            userDatabase.put("玥","666666");
        } catch (BindException e){
            System.out.println("请检查端口号，被占用~");
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
    public void start() {
        try {
            while(true) {
                System.out.println("等待客户端连接");
                Socket socket = serverSocket.accept();
                new Thread(new ClientHandler(socket)).start();
            }
        } catch (IOException e) {
            System.out.println("客户端链接断开链接~");
        } finally {
            if(serverSocket!=null&&!serverSocket.isClosed()){
                try {
                    serverSocket.close();
                } catch (IOException e) {
                    System.out.println("服务器关闭失败~~~");
                }
                System.out.println("服务器关闭成功~~Over");
            }
        }
    }
    public static void main(String[] args){
        new Server().start();
    }
    private boolean Login(String user,String pass){
        return userDatabase.containsKey(user)&&userDatabase.get(user).equals(pass);
    }
    private synchronized void broadcastMessage(String message){
        for(PrintWriter pw: allOut){
            pw.println("消息广播："+message);
        }
    }
    //2.广播在线用户列表方法  updateOnlineUsers 更新在线人数
    private synchronized void updateOnlineUsers (){
        synchronized (onlineUsers){
            String userList="在线用户："+String.join(".",onlineUsers);
            System.out.println(userList);
            broadcastMessage(userList);

        }
    }
    //提示：没有参数，传入字符串保存所有的客户端名称
    //2.1 String userList="在线用户"+String.join(",",onlineUsers);
    //理解：拼接字符串，来客户名，记录一个客户端名
    //2.2 来一个客户端，分发一个客户端消息：用户名消息

    private class ClientHandler implements Runnable {
        private Socket socket;
        private String ip;
        private PrintWriter pw;
        private BufferedReader br;
        private String username;
        private String password;
        public ClientHandler(Socket s) {
            this.socket = s;
            ip = socket.getInetAddress().getHostAddress();
            try {
                br = new BufferedReader(new InputStreamReader(socket.getInputStream(), "UTF8"));
                pw=new PrintWriter(new BufferedWriter(new OutputStreamWriter(socket.getOutputStream(),"UTF8")),true);
                synchronized (allOut){
                    allOut.add(pw);
                }
            } catch (IOException e) {
                System.out.println("客户端断开链接了~");
            }
        }

        private void handleChat(){
            new Thread(()->{
                try {
                    String message;
                    while ((message=br.readLine())!=null) {
                        System.out.println(ip+"客户端说：" + message);
                        System.out.print("服务器请输入：");
                        broadcastMessage(message);
                        updateOnlineUsers();
                    }
                } catch (IOException e) {
                    System.out.println("客户端发来的消息断开了~");
                }
            }).start();
            Scanner input=new Scanner(System.in);
            while(true){
                System.out.println("服务器请输入：");
                String sme=input.nextLine();
                pw.println("服务器说："+sme);
                if (sme.equalsIgnoreCase("exit")){
                    System.exit(0);
                }
            }
        }
        public void run() {
            try {
                pw.println("请输入用户名：");
                username=br.readLine();
                pw.println("请输入密码：");
                password=br.readLine();
                if(Login(username,password)){
                    pw.println("登录成功，欢迎进入XX牌聊天室");
                    //3.判断客户端链接成功--加入集合中   【同步块：监视对象】
                    //3.2 客户端登陆成功--名字加入集合中   方法？
                    onlineUsers.add(username);
                    synchronized (onlineUsers){
                        onlineUsers.add(username);
                        System.out.println("链接成功");
                        updateOnlineUsers();
                    }
                    handleChat();
                }else{
                    pw.println("登录失败，用户名或者密码错误！");
                    socket.close();  //关闭
                }
            } catch (IOException e){
                System.out.println("服务器端读写出问题！");
            } finally {
                //4.同步块--从集合中依次移除用户名
                synchronized (allOut){
                    allOut.remove(pw);
                }
                synchronized (onlineUsers){
                    onlineUsers.remove(username);
                }
                if(pw!=null)
                    pw.close();
                if (br != null)
                    try {
                        br.close();
                    } catch (IOException e) {
                        System.out.println("读入流断开链接~");
                    }
                if(socket!=null&&!socket.isClosed()){
                    System.out.println(ip+"客户端退出服务器链接~");
                    try {
                        socket.close();
                    } catch (IOException e) {
                        System.out.println(ip+"客户端退出链接异常~");
                    }
                }
            }
        }
    }
}



